Abrasive wheel



Patented Feb. 9, 1937 UNITED STATE.S

- z,oa9nss PATENT OFFICE 2,0s9nss ABRASIVE WIIEEL tion 013 Massachusetts Application August "l, 1935, Serial N0. 35,153

6 Claims. (01. 51-206) The invention relates to grlnding wheels and Wlth regard to lts more speclfic-features to grind- Ing wheels the central portlon of whlch constitutes' a non-abrasive -inetal disk.

Or'1e object 'of the inventlon is to proVide a practical construction for grlndlng wheels -of the type lndicated. Another object cf the invention ls to provlde a method of uniting an annular band of abraslvematerial to adisk center whlch is eoonomical in practice and which results in a s trong and true wheel, Another object of the invention is to prvide a unitary disk wheel construqtlon oi slight thickness andadequate strength. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists ir'1-the features of oorlstructlon, combinations of elements, arrangements of parts, and in the several steps and relation and order of ea.ch of said steps to 20 one or mute of the others thereof, all as will be lllustratively describedherein, and. the scope 013 the application of Which will be lndicated in the following clalms.

Ii1 the acconr xpanylng drawing in whi ch is 25 shown one of various possible embodlments of the mechanical 'features of this invention,

Fig. 1 is a sectional vtew of a portldn cf a .disk to which is to be united a grincling annu1us,

Flg. 2 is a sectional view of the structure shown 80 in Fig. 1, with the spllt' peripheral part of the disk expanded and a grindingannulusin' position to be secured 120 the disk,

Fig. 3 is a sec'cional view of the structure of Fig. 2 after the split peripheral portlonls closed 35 upon the annulus,

Fig. 4 is a sectional view of a grinding wheel corlstructed accordlng to the lnvention,

Fig. 5 ls a pl an or elevatlon 01 the wheel of Flg. 4, 40 Flg. 6 is a fragmentary sectional view slmilar to Fig. 3, illustrating a modification of the inventln.

Referrlng first to Fig. l, I provide 97 disk IlI.of

thln metal stock which may hav6, as shown in Figs. 4 and 5, a ;entral hole II for mountlng the completed wheel upon anairbor or central support of any sltable or desired type. For the disk III I preferably use soft steel but I- may also use non-ferrous metals such'as'aluminum copper, 50 brass or any other metal oralloy. In any suitable manner, such as by means of a kn ife or- 'gwedge or any cutting instrumentality, I form a groove.l2dn the priphery ofthe disk III. This groove I2", as. shown in Fig.l leaves a palr of- I3 parallel andspaced 3 perlpheral portions I 3,

apart. In order to form the groove I2 I may mount the disk II) upo'n an arbor, rotate it, and cut the groove with a very thin clrcular.saw guiding the edge of the disk III between rollers for accuracy. Or, on the other hand, I may use a thin grinding wheel to form the groove I2. Grinding wheels of any thickness deslr'ed from .006 upwards already exist and Ion the grinding of soft metals such as those indicated are highly efliclent. On the other hand, the grdove 10 I2 may be formed by spllttlng the metal as with a v steel knife blade or the like while the disk III is being rotatedlfdesired.

Having thus formed the peripheral portions I3, I separate them as shown in Fig. 2, or I may band them backwards untll they stand at right angles to the plane 015 the disk III. 'I'his may involve some puckering of the material on aCcount of the fact that the circumference is less as the diameter decreases, but this need not interfere with carrying out the method as will appear, I then introduce the disk III inside of an annulus I 5 comprising abrasive grit bonded with any suitable or known bond. Examples of abrasive grit aa1'e aluminum oxlde, sillcon carbide silicon dioxide, boron carbide and diamond. Examples 013 suitable bonds are shellac bonds, rubber bonds, natural and artificial riesi'nous bonds, ceramic bonds, metallic bonds and the like.

Referring now to Fig; 3, I close the periphe1al portions I3 over the inslde margin of the anr'1ulus I5. 'I'his may be done by mountingthe disk II) on the same or a different arbor, introducing rollers 'above and below the junctionpf dlsk and annulus and causing the rollers to approach while 5 rotating. 'U1tlmately enough p1essure should be exerted flrmlyto unite the parts mechanically. The rollers may be of large diameter and have grooves formed to correspond with the shape cf the parts shown in Flg. 3 and considerable pres- 40 sure may be used in thls rolling operation especially if the parts be carefully aligned arid if an abrasive annulus of somewh'at elastic properties be usgd. The'lnventlon lends itself particularly to the constructlon of a wheel including an abraslve annulus bonded with ai rubber or resinous bond which is not too brittle, sing ath'm wheels are particularly useful for cutting-ofli op erations im; sawlng and tfie l1ke and for su'ch a, resflient bond whlchwlll not break50.

purposes readily under stresses is preferred. Insteadlof r'ol1lrlg the peripheral portiorls I3, I3 onto the abraslva annulus I5, I may employ a swaging operation or the like.

Flg. 6 illustrate's a. modlflqtion of the inven-.

'where the Imetal center trating the diamond abrasive tion in which the abraslve annulus I 5 has a reduced portlon l! and the dlsk I8 has a -thickness slightly less than the thlckness o1 t he grindlng portion of the annulus IG. This results In a wheel partlcularly sulted for deep cuttlng operatlom !8 passes lnto the cut owmg to the depth thereof, because the .cut made I6 will be wider than the metal center at any point. Preferably the periphery o1 the annulus IG is .slightly wider than the comblned wldth of the portlons I9, I9 anti the portion l'l.

'I'he construction of the lnven'tlon len ds ltsel1' particularly t'o the construction of wheels the grinding portion of which comprlses diamond grit or abrasive bonded wlth slred bond, such as artlflclal reslnous material, for example. By the present construction, the grlnding annullls including' diamonds may be readily united to a metal center thus concengrit at the place of most efllciency. Furthermore, by t'ne use of a metal center a wheel which has a very large diameter relative to its thickness may be coustructed without impa-lring' its strength. 'I'he disk III is not brittle ls much reduced.

It will thus be seen that there has been proand thus breakage of wheels vided by this invention a method and artlcle in which the various objects hereinabove s et forth together with many thoroughly practlcal advantages are successtully achleved. As various possible embodlments mlght be made cf themechanical features of the above lnventlon und as the art herein descrlbed might be varied lnvarious parts, all without departing from the sc ope of the lnventlon, lt ls to be understood that all matter hereinbefore Set forth or shown in the accompanylng drawlng is 120 be interpreted as illustrative und not in a llmiting sense.

I claim:

' 1. The method of which comprlses forming a. groove in the perlphery o1 the dlsk, providing an annulus of abrasive substance bonded wi th a sultable band the inside dlameter of making a composi te whee l any sultable or dein parallel planes und providing a thin metal dlsk,

whlch ls sllghtly unter than the dlameter-of the disk lass twlce the depth o! the lng the meta.l on elther slde o1 the Ing the dl.sk In the .nnulus Ing the metal in place.

groove, und rolllng o: waggroove, Open- 2. A grlndlng wheel comprlslng a metal center,

center und annulus comprlslng split perlphera.l portlons of the center surroundlhg und grlpplng the lnner marginal Sldes ot the annulus. the metal center and the sald perlpheral portlons constltuting an integral plece.

3. An abraslvewheel comprlsing a soft inetal portlon and belng metal disk having a central hole sald dlsk havlng its side faces in parallel Planes, anannulus 'of bonded abraslve n'1aterlal of a thlckness substantially that o1 the dlsk und havlng lts slde faces the radial dimenslon o1 y the cut or groove lylng on' wlth the annulus, the sa.ld

sal' annuls beingsubstanttal es compared-to the thickness thereof und a groove extendlng peripherally around the dlsk und separatlng the metal of the' dlsk at the perlphery lnto perlpheral portlons whichlle in parallel relatlon in engagement wlth the annulus, holdlng the annulus to the disk.

6. An abiaslve wheel as clalmed in clalm 5 in which the inner pa.rt ol the annulus is reduced in thickness so that the outsld.e surfaces of the perlpheral portlons are flush wlth the outer surfa'ces of the dlsk and of the abraslve annulus.

EDWARD VAN nln PYL. 

